Ok, we try.
Faraday's law of induction and because of energy storage by the inductance;
v
l = L (di/dt). -Defines what "L" is via the voltage across the inductance assuming a hypothetical zero resistance of course.
Now when you look at with a frequency added component you are transformed into the world of Reactances and Impedances.
First let's assume a steady state sinusoidal voltage and current.
i = Ie
jwt. ( that "w" is omega or 2pi*f)
And di/dt = jwIe
jwtThen V
Le
jwt = jwLIe
jwtAlready you can see that di/dt is frequency dependent.
Moving right along, canceling the exponential,
V
L = jwLI. Which expression resembles ohms law where wL looks like R but is now called reactance and is directed in quadrature by "j".
So you'll correct me if I'm wrong but the relationship to me states that if "w" or 2 pi * F, or just freq. is greater across a given winding, then V
L is greater, that is more energy across that coil at 800cps vs. 60cps which certainly will help trigger that lil' baby. ..transferred into the mechanical domain, just plain more scrote.
Well I digressed somewhat. The question was varying torque, not the definition of inductive reactance.
But you can see where the thought process, the original statement initially railed.
And do you know how long it took to write this on an iPad? --Never again.